Electric switch



Inveni'or William K. Rankin,

His ATi'orne y.

W. K. RANKlN ELECTRIC SWITCH Dec. 4, 1928.

:TITIT m m w control of Patente -pee.- '4; 192a UNITED-STATES WILLIAM-x, mm; or scorn, New xonx, ASSIGNOR'1O 1 commmr, A conronarron or NEW you. x

, v 1,694,282 "PATENT" orr cs.

G m mnc'rme l1 amc'rnrc swrrcrt Application filed Augusta), 1926. Serial no. 132,425. I

, My invention relates to electric switches,

particularly of the type adapted for the heavy overload or shortcircuit currents without damage tothe apparatus or danger to attendants.

My invention. will be better understood from the following description, takenin'con- .nection with the accompanying drawing, and

its scope will be pointed out in the appended claims. I

In the drawing, Fig. 1 is a vertical sectional view of onefformof m invention,'and

Fig. 2 is an elevation part y in section at right angles to Fig. 1 and drawn to a smaller scale.

Referring to the drawing, the vessel or tank 1 has a cover 2 and contains the insulating l iquid 3. Passing through the'cover'2 are the two insulator bushin s 4 and 4 through which extend the con uctors 5 and 6 for connection wtih. the; switch contacts. The supporting base 8, through which extends the passage 9, supports at one end the inter-- v rupting chamber 10 by means of the ,insu

x lator 11 and insulator clam '12, the chamber top .of the chamber is a small valve.22 forallowing the escape of gas therefrom and the mental contacts 19."

being held down on the insu ator by the sleeve 13. 'Inthe lower end of the interrupting chamber is mounted the segmental socket contact member 15 which isjthe' fixed contact of the'switch and which is adpated to receive the movable contact rod '16. The

socket contact member 15' is connected to conductor 6 by means of contact plate 17, andcontact rod-16 is connected to conductor 5 by means of contact late 18 and the segithin the chamber 10 is a bafiie 20 and supports 21, and in the lower portion by the insulator 29. The con tact rod 16 is retained in its u per position by-the plate thereon engaglng the catch 31 mounted in the protective cap 32. The

gh potentlal large capacity'cir-' cuits. An object of my invention is the provision of an improved switch of thischar-p 'acter which shall be capable of interrupting as illustrated, the releaseof the late catch ma be withdrawn and the contact released y means of a handle 33 or by any I other suitable manual or automatic reclosing means. a

An important feature otm invention is. that the movable contact ro is" separated from the fixed contact by the force of insulating liquid directed against it, and the arrangement is such that after separation of the contacts any. are that is drawn therebetween is extinguished by a high pressure stream of liquid which is'forced through the. fixed socket contact member toward .the moving contact rod. As a means of furnishing the necessary liquid pressure, I have shown by way of example a sprin actuated pump arranged in the tank. 1. cylinder 36'is secured to the base 8 with its bore connecting with the passage 9and near its upper end has small openings 37 which are uncovered when the piston 38 is iii its he pump elevated position. The piston rodv 39 extends on up throughthe stufiing box 40 in the cover 2 and terminates in an enlargement 41 which has a cam face 42 for a purose to be described later. Plate 43 secured y the rods 44 to the base 8 and having an- 2 opening through which the piston rod passes serves as an abutment for one end of the heavy coil spring 45 which bears at its other end on the'flange 46 of the piston and which is compressed when the piston is raised to the position illustrated. Any suitable means may be employed .for raising the piston against the spring, which means may connect with the piston rodthrough the. eye 47. For retaining the piston in its upward position I have 'shown a latching device comprising the bell crank-lever 48 an'd'lever. 49 each havin a roller 50 engaging the cam 'face '42 an connected to act in unison by by the switch, as "for example a predetermined overload, or it may be manually operated if desired.

With the switch in closed. circuit osition,

iiing device by a buckling of the toggle 52 allowsthe spring 45 to drive the piston 38 down with considerable force. The insulating liquid thereby forced into the interrupting chamber and against the end of the contact rod 16 drives the rod upward out of engagement with the socket contact member 15 compressing the closing spring 28. Slight leakage around the contact rod closes the valve At the upper end of its travel, the rod is retained by the latch 81 against reclosing. it Willbe seen that by this construction the contact rod upon leaving the socket contact is follovted by a stream or" relatively cool insulating liquid under considerable pressure; Any are that may be drawn between the contacts is thereby subjected to this high pressure stream of cool insulating liquid and is quickly extinguished. While the switch is held open the piston may be raised to the position shown to compress the actuating spring preparatory to a subsequent closing operation. In this position or" the piston the openings 3? in the cylinder are uncovered so that the pressure of gas formed in the chamber '10 is relieved, whereupon the small valve 22 opens and allows the gas in th chamber to escape d the chamber to r with liquid. if 'L e switch is tripped open by a heavy overload or short circuit, the volume of gas format in the chamber may produce a greater pressure than the spring actuated pump, in which case the liquid may flow back i to the pump cylinder compressin the sp until it escapes through the openings To effect a reclosing of the switch, the latch 31 is Withd arm to allow the spring 28 force the contact rod 16 down into circuit closing position. this operation liquid displaced by the rod escapes also through openings g'i' What 1 claim as new, by Letters Fatent of I tending into 1. An electric switch comprising an enclosingvessel adapted to contain an insulating liquid, an interrupting chamber therein having a fixed socket contact member at one end thereof, a cooperating movable contactrod extending through the opposite end thereof, a pump in the vessel communication With the I ianiber whereby liquid forced into the chamber separates the contacts and flows through the socket contact member, a spring for oper ting the pump and load responsive me eleasing the spring.

2. in electric s tch comprising an enclosing vessel containing insulatin liquid, an interrupting chamber therein having 'a fixed contact, a cooperating contact rod exthe chamber, a pump immersed in said vessel and connected to point opposite the end of energy storing means for actuating said pump.

3. an electric itch comprising an enclosing vessel 1 n insulating liquid,

in the liquid the chamber the contact :o

er immersed in the operating contact other end of the wing a cylinder 1miquid and having said cylinder having 'e: o ening therein arranged by the piston in its initial tora spring for operating said cad responsive means for 1 BANKER 

